| 摘要 |
PURPOSE:To improve the system operating efficiency by forming a main data signal into a polyphase PSK wave being >=4 PSK in the transmission system where a sub-data signal is transmitted compositely to a main data line using PSK modulation. CONSTITUTION:An input signal enters an orthogonal demodulator 1, where the signal is detected with delay or detected synchronizingly and the signal is converted into two demodulating signals P, Q being mutually in orthogonal relation. The P, Q signls enter a phase shifter comprising resistors 2-5 adders 6, 7, and subtractors 8, 9 and converted into output signals 101-104 having four phase relations. These signals are multiplied by multipliers 10-12 by 4-multiple to the input signal. Then, the main data signal is eliminated and only the sub- data signal remains. Further, the signals P, Q are formed into signals 108, 109 delayed respectively by pi/4 radian through multipliers 15, 16 and selected by the sub-data signal at analog switches 17, 18. |
